A small Bash script to grep over APKs after uncompressing them

dex_grepper.sh

#!/bin/bash
#set -x
 
if [[ $# -ne 2 ]]; then
    echo "Usage: $0 <grep_regex> <dir>"
    echo "Search for APKs in a directory, extract the dex from them and grep over them for a pattern"
    echo "    <grep_regex> The regex that will be passed to 'grep -ial' upon APKs "
    echo "    <dir>        The directory to 'find' APKs in"
    exit 1
fi
 
re=$1; dir=$2
for apk in `find $dir -name "*.apk" -type f`; do
    unzip -qq -o -d /tmp $apk "*.dex" 2>/dev/null
    if grep -qial "$re" /tmp/*.dex 2>/dev/null; then
        echo "$apk matched!"
    else
        unzip -qq -o -d /tmp $apk "*.so" 2>/dev/null 
        if grep -rqial "$re" /tmp/lib/ 2>/dev/null; then
            echo "$apk matched!"
        fi
        rm -fr /tmp/lib/
    fi
    rm -f /tmp/*.dex
done 

gistfile1.txt

Run it on extracted, mounted system images or inside the whole /system/priv-app directory of a working device

$ ./dex_grepper.sh semobileservicesessionimpl /media/S8priv_app/
/media/S8priv_app/system/priv-app/SamsungContacts/SamsungContacts.apk matched!
/media/S8priv_app/system/priv-app/SecGallery2015/SecGallery2015.apk matched!
/media/S8priv_app/system/priv-app/Messaging_SEP81/Messaging_SEP81.apk matched!